In light-emitting diode or device (LED) lighting applications, optic is designed around an LED die to achieve a certain degree of control to where the light is directed. The optics is often mounted separately from the LED die. To reduce this two-stage assembly, an overmold optic is designed to integrate the optic and the LED die. One example of overmold optics is the hemispherical dome molded over the die that increases the extraction efficiency of the LED die but does not redirect the light. Another example is the side-emitter overmold optic that both increases the extraction efficiency and redirects the light from the LED die to deform the radiation pattern from Lambertian to side emitting.
FIG. 1 illustrates a conventional LED package 100. Package 100 includes a heat sink 102, LED dies 104 (only one is labeled), primary optics 106 (only one is labeled) on LED dies 104, and a secondary optic 108 mounted on heat sink 102. LED die 104 may include an LED and a wavelength converter, such as a ceramic phosphor, on the LED. Primary optics 106 are hemispherical dome overmolds that help to extract light from LED dies 104 but does redirect the extracted light. Secondary optic 108 is a reflector that collimates the extracted light as shown in the intensity slice diagram on the figure. Note that 0 degrees corresponds to a direction perpendicular to the top surface of the LED die 104.